Effects of Evidence-Based Fall Reduction Programing on the Functional Wellness of Older Adults in a Senior Living Community: A Clinical Case Study.

BACKGROUND: Older adults at a high risk of falls may be referred to a physical therapist. A physical therapy episode of care is designed for the transition of an older adult from a high fall risk to a moderate to low fall risk. However, these episodes of care are limited in time and duration. There is compelling evidence for the efficacy of group-based exercise classes to address risk, and transitioning an older adult from physical therapy to a group-based program may be an effective way to manage risk through the continuum of care. OBJECTIVES: The purpose of this study was to translate research findings into a real world setting, and demonstrate the efficacy of integrating evidence-based fall prevention exercises into pre-existing exercise classes at a senior living facility as a proof of concept model for future programing. METHODS: Twenty-four participants aged 65 years and older living in a senior living community and the community were stratified into group-based exercise classes. Cutoff scores from functional outcome measures were used to stratify participants. Exercises from The Otago Exercise Program were implemented into the classes. Functional outcome measures collected included the 10-Meter Walk Test, 30-Second Sit to Stand, and Timed Up and Go (TUG). Number of falls, hospitalizations, and physical therapy episodes of care were also tracked. Data were compared to a control group in a different senior living community that offered classes with similar exercises aimed at improving strength and mobility. The classes were taught by an exercise physiologist and were of equal duration and frequency. RESULTS: Participants demonstrated significant improvements in all functional outcome measures. TUG mean improved from 13.5 to 10.4 s (p = 0.034). The 30-Second Sit to Stand mean improved from 10.5 to 13.4 (p = 0.002). The 10-Meter Walk Test improved from 0.81 to 0.98 m/s (p \u3c 0.0001). Participants did not experience any falls or hospitalizations, and two participants required physical therapy episodes of care. CONCLUSION: Implementing an evidence-based fall reduction program into a senior living program has a positive effect on strength, balance, fall risk, gait speed, fall rate, hospitalizations, and amount of physical therapy intervention

Predicting the hypervelocity star population in Gaia

Hypervelocity stars (HVSs) are amongst the fastest objects in our Milky Way. These stars are predicted to come from the Galactic center (GC) and travel along unbound orbits across the Galaxy. In the coming years, the ESA satellite Gaia will provide the most complete and accurate catalogue of the Milky Way, with full astrometric parameters for more than $1$ billion stars. In this paper, we present the expected sample size and properties (mass, magnitude, spatial, velocity distributions) of HVSs in the Gaia stellar catalogue. We build three Gaia mock catalogues of HVSs anchored to current observations, exploring different ejection mechanisms and GC stellar population properties. In all cases, we predict hundreds to thousands of HVSs with precise proper motion measurements within a few tens of kpc from us. For stars with a relative error in total proper motion below $10 \%$, the mass range extends to ~$10 M_{\odot}$ but peaks at ~$1$ $M_\odot$. The majority of Gaia HVSs will therefore probe a different mass and distance range compared to the current non-Gaia sample. In addition, a subset of a few hundreds to a few thousands of HVSs with $M$ ~ $3$ $M_\odot$ will be bright enough to have a precise measurement of the three-dimensional velocity from Gaia alone. Finally, we show that Gaia will provide more precise proper motion measurements for the current sample of HVS candidates. This will help identifying their birthplace narrowing down their ejection location, and confirming or rejecting their nature as HVSs. Overall, our forecasts are extremely encouraging in terms of quantity and quality of HVS data that can be exploited to constrain both the Milky Way potential and the GC properties.Comment: 17 pages, 18 figures, accepted for publication in MNRA

Constraining blazar distances with combined Fermi and TeV data: an empirical approach

We discuss a method to constrain the distance of blazars with unknown redshift using combined observations in the GeV and TeV regimes. We assume that the VHE spectrum corrected for the absorption through the interaction with the Extragalactic Background Light can not be harder than the spectrum in the Fermi/LAT band. Starting from the observed VHE spectral data we derive the EBL-corrected spectra as a function of the redshift z and fit them with power laws to be compared with power law fits to the LAT data. We apply the method to all TeV blazars detected by LAT with known distance and derive an empirical law describing the relation between the upper limits and the true redshifts that can be used to estimate the distance of unknown redshift blazars. Using different EBL models leads to systematic changes in the derived upper limits. Finally, we use this relation to infer the distance of the unknown redshift blazar PKS 1424+240.Comment: 5 pages, 4 figures, accepted for publication in MNRAS, minor revisio

The low wind expansion velocity of metal-poor carbon stars in the Halo and the Sagittarius stream

We report the detection, from observations using the James Clerk Maxwell Telescope, of CO J $=$ 3$\to$ 2 transition lines in six carbon stars, selected as members of the Galactic Halo and having similar infrared colors. Just one Halo star had been detected in CO before this work. Infrared observations show that these stars are red (J-K $>$3), due to the presence of large dusty circumstellar envelopes. Radiative transfer models indicates that these stars are losing mass with rather large dust mass-loss rates in the range 1--3.3 $\times$$10^{-8}$M$_{\odot}$yr$^{-1}$, similar to what can be observed in the Galactic disc. We show that two of these stars are effectively in the Halo, one is likely linked to the stream of the Sagittarius Dwarf Spheroidal galaxy (Sgr dSph), and the other three stars certainly belong to the thick disc. The wind expansion velocities of the observed stars are low compared to carbon stars in the thin disc and are lower for the stars in the Halo and the Sgr dSph stream than in the thick disc. We discuss the possibility that the low expansion velocities result from the low metallicity of the Halo carbon stars. This implies that metal-poor carbon stars lose mass at a rate similar to metal-rich carbon stars, but with lower expansion velocities, as predicted by recent theoretical models. This result implies that the current estimates of mass-loss rates from carbon stars in Local Group galaxies will have to be reconsidered.Comment: 10 pages, 7 figures, accepted for publication in MNRA

Violation of the isotropic-ℓ\ell approximation in overdoped La_{2-x}Sr_xCuO_4

Magnetotransport measurements on the overdoped cuprate La_{1.7}Sr_{0.3}CuO_4 are fitted using the Ong construction and band parameters inferred from angle-resolved photoemission. Within a band picture, the low temperature Hall data can only be fitted satisfactorily by invoking strong basal-plane anisotropy in the mean-free-path $\ell$. This violation of the isotropic-$\ell$ approximation supports a picture of dominant small-angle elastic scattering in cuprates due to out-of-plane substitutional disorder. We show that both band anisotropy and anisotropy in the elastic scattering channel strongly renormalize the Hall coefficient in overdoped La_{2-x}Sr_xCuO_4 over a wide doping and temperature range.Comment: 4 pages, 4 figure

Combinatorial Games with a Pass: A dynamical systems approach

By treating combinatorial games as dynamical systems, we are able to address a longstanding open question in combinatorial game theory, namely, how the introduction of a "pass" move into a game affects its behavior. We consider two well known combinatorial games, 3-pile Nim and 3-row Chomp. In the case of Nim, we observe that the introduction of the pass dramatically alters the game's underlying structure, rendering it considerably more complex, while for Chomp, the pass move is found to have relatively minimal impact. We show how these results can be understood by recasting these games as dynamical systems describable by dynamical recursion relations. From these recursion relations we are able to identify underlying structural connections between these "games with passes" and a recently introduced class of "generic (perturbed) games." This connection, together with a (non-rigorous) numerical stability analysis, allows one to understand and predict the effect of a pass on a game.Comment: 39 pages, 13 figures, published versio

An X-ray measurement of Titan's atmospheric extent from its transit of the Crab Nebula

Saturn's largest satellite, Titan, transited the Crab Nebula on 5 January 2003. We observed this astronomical event with the {\it Chandra} X-ray Observatory. An ``occultation shadow'' has clearly been detected and is found to be larger than the diameter of Titan's solid surface. The difference gives a thickness for Titan's atmosphere of 880 $\pm$ 60 km. This is the first measurement of Titan's atmospheric extent at X-ray wavelengths. The value measured is consistent with or slightly larger than those estimated from earlier Voyager observations at other wavelengths. We discuss the possibility of temporal variations in the thickness of Titan's atmosphere.Comment: 14 pages, 5 figures, AASTeX preprint. Accepted for publication in the Astrophysical Journa